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<div class="title">segment2.cpp</div>  </div>
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<a href="segment2_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;</div>
<div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="__gbmath_8h.html" title="MAIN INCLUDE HEADER. ">_gbmath.h</a>&quot;</span></div>
<div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160; </div>
<div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160; </div>
<div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160; </div>
<div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="keyword">namespace </span>gbmath</div>
<div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;{</div>
<div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;        </div>
<div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;</div>
<div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;</div>
<div class="line"><a name="l00011"></a><span class="lineno"><a class="code" href="namespacegbmath.html#a87cb40f66df9d4de36ac2a769abf3a32">   11</a></span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> <a class="code" href="namespacegbmath.html#a87cb40f66df9d4de36ac2a769abf3a32">__dt1_IsPointInBoundingBox</a>(<span class="keywordtype">float</span> x1, <span class="keywordtype">float</span> y1, <span class="keywordtype">float</span> x2, <span class="keywordtype">float</span> y2, <span class="keywordtype">float</span> px, <span class="keywordtype">float</span> py)</div>
<div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;{</div>
<div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;    <span class="keywordtype">float</span> left, top, right, bottom; <span class="comment">// Bounding Box For Line Segment</span></div>
<div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;</div>
<div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;    <span class="comment">// For Bounding Box</span></div>
<div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;    <span class="keywordflow">if</span>(x1 &lt; x2)</div>
<div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;    {</div>
<div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;        left = x1;</div>
<div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;        right = x2;</div>
<div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;    }</div>
<div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;    <span class="keywordflow">else</span></div>
<div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;    {</div>
<div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;        left = x2;</div>
<div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;        right = x1;</div>
<div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;    }</div>
<div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;</div>
<div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;    <span class="keywordflow">if</span>(y1 &lt; y2)</div>
<div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;    {</div>
<div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;        top = y1;</div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;        bottom = y2;</div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;    }</div>
<div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;    <span class="keywordflow">else</span></div>
<div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;    {</div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;        top = y2;</div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;        bottom = y1;</div>
<div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;    }</div>
<div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;</div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;    <span class="keywordflow">if</span>( (px+0.01) &gt;= left &amp;&amp; (px-0.01) &lt;= right &amp;&amp; </div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;        (py+0.01) &gt;= top &amp;&amp; (py-0.01) &lt;= bottom )</div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;    {</div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;        <span class="keywordflow">return</span> 1;</div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;    }</div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;    <span class="keywordflow">else</span></div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;        <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;</div>
<div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;}</div>
<div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;</div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;</div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;</div>
<div class="line"><a name="l00050"></a><span class="lineno"><a class="code" href="namespacegbmath.html#a629a1e67ad42dd4536a582f28491a13b">   50</a></span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> <a class="code" href="namespacegbmath.html#a629a1e67ad42dd4536a582f28491a13b">LineSegmentIntersection</a>(<span class="keywordtype">float</span> l1x1, <span class="keywordtype">float</span> l1y1, <span class="keywordtype">float</span> l1x2, <span class="keywordtype">float</span> l1y2,</div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;    <span class="keywordtype">float</span> l2x1, <span class="keywordtype">float</span> l2y1, <span class="keywordtype">float</span> l2x2, <span class="keywordtype">float</span> l2y2,</div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;    <span class="keywordtype">float</span> *m1, <span class="keywordtype">float</span> *c1, <span class="keywordtype">float</span> *m2, <span class="keywordtype">float</span> *c2,</div>
<div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;    <span class="keywordtype">float</span>* intersection_X, <span class="keywordtype">float</span>* intersection_Y)</div>
<div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;{</div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;</div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;    <span class="keywordtype">float</span> dx, dy;</div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;</div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;    dx = l1x2 - l1x1;</div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;    dy = l1y2 - l1y1;</div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;</div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;    *m1 = dy / dx;</div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;</div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;    <span class="comment">// y = mx + c</span></div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;    <span class="comment">// intercept c = y - mx</span></div>
<div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;    *c1 = l1y1 - *m1 * l1x1; <span class="comment">// which is same as y2 - slope * x2</span></div>
<div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;</div>
<div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;    dx = l2x2 - l2x1;</div>
<div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;    dy = l2y2 - l2y1;</div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;</div>
<div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;    *m2 = dy / dx;</div>
<div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;    <span class="comment">// y = mx + c</span></div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;    <span class="comment">// intercept c = y - mx</span></div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;    *c2 = l2y1 - *m2 * l2x1; <span class="comment">// which is same as y2 - slope * x2</span></div>
<div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;</div>
<div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;    <span class="keywordflow">if</span>( (*m1 - *m2) == 0)</div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;        <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;    <span class="keywordflow">else</span></div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;    {</div>
<div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;        *intersection_X = (*c2 - *c1) / (*m1 - *m2);</div>
<div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;        *intersection_Y = *m1 * *intersection_X + *c1;</div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;    }</div>
<div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;</div>
<div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;    <span class="keywordflow">if</span>(<a class="code" href="namespacegbmath.html#a87cb40f66df9d4de36ac2a769abf3a32">__dt1_IsPointInBoundingBox</a>(l1x1, l1y1, l1x2, l1y2, *intersection_X, *intersection_Y) == 1 &amp;&amp; <a class="code" href="namespacegbmath.html#a87cb40f66df9d4de36ac2a769abf3a32">__dt1_IsPointInBoundingBox</a>(l2x1, l2y1, l2x2, l2y2, *intersection_X, *intersection_Y) == 1)</div>
<div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;    {</div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;        <span class="keywordflow">return</span> 1;</div>
<div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;    }</div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;    <span class="keywordflow">else</span></div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;        <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;}</div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;</div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;</div>
<div class="line"><a name="l00092"></a><span class="lineno"><a class="code" href="classgbmath_1_1segment2.html#a57f27dd14c9c09c8850fff9fe390e70a">   92</a></span>&#160;<span class="keywordtype">bool</span> <a class="code" href="classgbmath_1_1segment2.html#a57f27dd14c9c09c8850fff9fe390e70a">segment2::IsIntersection</a>( <span class="keyword">const</span> <a class="code" href="classgbmath_1_1segment2.html">segment2</a>&amp; s2,  <a class="code" href="structgbmath_1_1vec2.html" title="2d-base vector. Corrected by operators epislon ">vec2</a>&amp; pIntersect )</div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160;{</div>
<div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160; </div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;    <span class="keywordtype">float</span> m1, c1, m2, c2;</div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;    <span class="keywordtype">float</span> intersection_X, intersection_Y;</div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;</div>
<div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;    <span class="keywordtype">int</span> res = <a class="code" href="namespacegbmath.html#a629a1e67ad42dd4536a582f28491a13b">LineSegmentIntersection</a>( <a class="code" href="classgbmath_1_1segment2.html#ac4926112e09d4c179826438842f4c190">p1</a>.<a class="code" href="structgbmath_1_1vec2.html#a86ff75c64d87662abfee8c35c5a343d0">x</a> , <a class="code" href="classgbmath_1_1segment2.html#ac4926112e09d4c179826438842f4c190">p1</a>.<a class="code" href="structgbmath_1_1vec2.html#a9212649e2705d2216739fc89763f00b6">y</a> , <a class="code" href="classgbmath_1_1segment2.html#a9b753911ec3560ac88cf630a557a9fd6">p2</a>.<a class="code" href="structgbmath_1_1vec2.html#a86ff75c64d87662abfee8c35c5a343d0">x</a> , <a class="code" href="classgbmath_1_1segment2.html#a9b753911ec3560ac88cf630a557a9fd6">p2</a>.<a class="code" href="structgbmath_1_1vec2.html#a9212649e2705d2216739fc89763f00b6">y</a> , </div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;        s2.<a class="code" href="classgbmath_1_1segment2.html#ac4926112e09d4c179826438842f4c190">p1</a>.<a class="code" href="structgbmath_1_1vec2.html#a86ff75c64d87662abfee8c35c5a343d0">x</a> , s2.<a class="code" href="classgbmath_1_1segment2.html#ac4926112e09d4c179826438842f4c190">p1</a>.<a class="code" href="structgbmath_1_1vec2.html#a9212649e2705d2216739fc89763f00b6">y</a> , s2.<a class="code" href="classgbmath_1_1segment2.html#a9b753911ec3560ac88cf630a557a9fd6">p2</a>.<a class="code" href="structgbmath_1_1vec2.html#a86ff75c64d87662abfee8c35c5a343d0">x</a> , s2.<a class="code" href="classgbmath_1_1segment2.html#a9b753911ec3560ac88cf630a557a9fd6">p2</a>.<a class="code" href="structgbmath_1_1vec2.html#a9212649e2705d2216739fc89763f00b6">y</a> ,</div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;        &amp;m1, &amp;c1, &amp;m2, &amp;c2,</div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;        &amp;intersection_X, &amp;intersection_Y</div>
<div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;        );</div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;</div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;    pIntersect.<a class="code" href="structgbmath_1_1vec2.html#a86ff75c64d87662abfee8c35c5a343d0">x</a> = intersection_X;</div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;    pIntersect.<a class="code" href="structgbmath_1_1vec2.html#a9212649e2705d2216739fc89763f00b6">y</a> = intersection_Y;</div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;</div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;    <span class="keywordflow">return</span> res != 0;</div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;}</div>
<div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;</div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;</div>
<div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;</div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;</div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;</div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;</div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;}</div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;</div>
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